The bike sensor provides data of speed and cadence when you ride Bike Trainer, can connect with riding APP by BT. The speed or cadence mode for you to select. Features: Using BT BLE4.0 and ANT+ dual-mode technology, it can connect with bike computer that conforms tostandard BT protocol and ANT+ protocol. Cordless connect with riding APP and make data transfer, currently support for Wahoo, Cateye, Topeak, Teasi,Komoot, Falk, Meilan, Shealth APP etc. Using software intelligent algorithm, automatically measure speed and cadence; suitable for cycling or spinningin a gym. The device has a quick button, you can quickly select the speed or cadence mode, and there are two instruction lights corresponding to the different working conditions. Cadence with white light, speed with green. Using coin cell CR2032, easy replacement, it can be used about 9 months continuously. Waterproof IPX5, worry free using in heavy rain. Easy installation, 3 seconds to go. Specifications: : Meilan Model: C1 Material: ABS Color: Black Waterproof: IPX5 BT Version: 4.0 Package Weight: 15g / 0.53ounces Package Size: 80 * 70 * 20mm / 3.15 * 2.76 * 0.79in Note: MEILAN C1, C3, M4 are used for bike trainer, maybe not suitable for your spin bike to install, please consider. The device is one channel output, at the same time can only choose one of Speed or Cadence. Package List: 1 * Speed Sensor 2 * Rubber Bands